I have a AWS accound and I have installed ES there under /dev/elk folder ..
It was fine for a long period of time but few days ago somehow the files were deleted.
I assume you mean that you have an EC2 and installed elasticsearch onto it.
What is the type of the root partition of your EC2? Is it EBS or is it AWS Instance Store? If it's Instance Store, then it is ephemeral and can go away at any time.
See here and here for a description of the differences between EBS and Instance Store.
Without more information about how you launched the ec2, how you provisioned it etc it is difficult to provide a more in-depth answer.
Related
We have an EC2 instance running in AWS EC2 instance. We have our ML algorithms and data that. We have also hosted a web-based interface also in that machine.
Now there are no new developments happening in that EC2 instance. We would like to terminate AWS subscription for a short period of time (for the purpose of cost-reduction and exploring new cloud services). Most importantly, we want to be in a position where we can purchase a new EC2 instance with a fresh AWS subscription, use the backup which we take now, and resume all operations (web-backend, SMS services for our app which is hosted in AWS, etc.).
What is the best way to do it? Is temporary termination of AWS subscription advisable?
There is no concept of an "AWS Subscription". AWS is charged on-demand, which means you only pay when you use resources.
If you temporarily do not want the Amazon EC2 instance, you could:
Stop the instance, which is like turning off the power. You will not be charged for the instance, but you will still pay for the disk storage attached to the instance. You can simply Start the instance again when you wish to use it. You will only be charged while the instance is running. OR
Create an image of the instance, then terminate the instance. This will create an Amazon Machine Image (AMI), which contains a copy of the disks. You can then launch a new Amazon EC2 instance from the AMI when you wish to use it again. This is a lower-cost option compared to simply stopping the instance, but it takes more effort to stop/start.
It is quite common for companies to stop Amazon EC2 instances at night or over the weekend to reduce costs while they are not needed.
EDIT: Just thought of a third option. Will test it and be back. Not worth it; it would involve creating an image from the EC2 instance and then convert that image to a VM image, storing the VM image in S3. There may be some advantages to this, but I do not see them.
I think you have two options, both of them very reasonably priced. If you can separate the data from the operating system, then your best option would be to use an S3 bucket as a file system within the EC2 instance. Your EC2 instance would use this bucket to store all your "ML algorithms and data" and, possibly, even your "web-based interface". Whenever you decide that you no longer need the processing capacity of the EC2, you would unmount the S3 bucket file system from the EC2 instance and terminate that instance. After configuring an appropriate lifecycle rule for the S3 bucket, it would transition to Glacier, or even Glacier Deep Archive [you must considerer the different options of long term storage]. In the future, whenever you want to work with your data again, you would move your data from Glacier back to S3, create a new EC2 instance, install your applications, mount your S3 bucket as a file system and you would have access to all your data. I think this is your least expensive and shortest recovery time objective option. To implement this option, look at my answer to this question; everything you need to use an S3 bucket as a regular folder inside the EC2 instance is there.
The second option provides an integrated solution, meaning the operating system and the data stay together, and allows you to restore everything as it was the day you stopped processing your data. It's made up of the following cycle:
Shutdown your EC2 and make a note of all the specs [you need them further down].
Export your instance to a virtual image, vmdk for example, and store it in your S3 bucket. Something like this:
aws ec2 create-instance-export-task --instance-id i-0d54b0682aa3998a0
--target-environment vmware --export-to-s3-task DiskImageFormat=VMDK,ContainerFormat=ova,S3Bucket=sm-vm-backup,S3Prefix=vms
Configure an appropriate lifecycle rule for the S3 bucket so that it transitions to Glacier, or even Glacier Deep Archive.
Terminate the EC2 instance.
In the future you will need to implement the inverse, so you will need to restore the archived S3 Object [make sure you you can live with the time needed by AWS to do this]
Import the virtual image as an EC2 AMI, something like this [this is not complete - you will need some more options that you saved above]:
aws ec2 import-image --disk-containers
Format=ova,UserBucket="{S3Bucket=sm-vm-backup,S3Key=vmsexport-i-0a1c382e740f8b0ee.ova}"
Create an EC2 instance based on the image and you're back in business.
Obviously you should do some trial runs and even automate the entire process if it's something that will be done frequently. I have a feeling, based on what you said, that the first option is a better option, provided you can easily install whatever applications they use.
I'm assuming that you launched an EC2 instance from a base Amazon Machine Image and then added your own software and models to it. As opposed to launched an EC2 instance from an AWS Marketplace offering.
The simplest thing to do is to create an Amazon Machine Image (AMI) from your running EC2 instance. That will capture the current state of the instance and persist it in your AWS account. Then you can terminate the instance. Later, when you want to recreate it, launch a new instance, selecting the saved AMI instead of a standard AMI.
An alternative is to avoid the need to capture machine state at all, by using standard DevOps practices to revision-control everything you need to recreate the state of a running machine.
Note that there are costs associated with an AMI, though they are minimal ($0.05 per GB-month of data stored, for example).
I had contacted AWS customer care regarding this issue. Given below is the response I received. Please add your comments on which option might be good for me.
Note: I acknowledge the AWS customer care team for their help.
I understand that you require some information on cost saving for your
Instance since you will not be utilizing the service for a while.
To assist you with this I would recommend checking out the Instance
Stop/Start link here:
==>https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/Stop_Start.html .
When you stop an Instance, you do not lose any data & you are not
charged for the resources any further. However please keep in mind
that you will still be charged for any EBS Storage Volumes attached to
the stopped Instance(s).
I also recommend checking out the below links on how you can reduce
your costs.
==>https://aws.amazon.com/premiumsupport/knowledge-center/reduce-aws-bill/
==>https://aws.amazon.com/blogs/compute/10-things-you-can-do-today-to-reduce-aws-costs/
That being said, please note that as I am in the billing department,
for the best assistance with the various plans you will require the
assistance of our Sales Team.
The Sales Team will be able to assist with ways to save while
maintaining your configurations.
You will be able to reach the Sales Team here:
==>https://aws.amazon.com/websites/contact-us/.
Once you have completed the details in the link, a member of the team
will be in touch with you at their soonest.
I upgraded an AWS EC2 machine 10 days ago (from t2-medium to t2-large). Again, I just upgraded today the same AWS EC2 machine (from t2-large to t2-xlarge) and after rebooting I noticed a massive loss of data (10 days of work). In fact, after changing instance type I found out it reverted to the same "state" of the machine just after doing the upgrade 10 days ago. Not less important, I have been doing snapshots periodically (twice a day), and when I try to recover from the last one, each snapshot is an exact copy of the machine after the first upgrade.
This is not the first project I have in AWS, and everytime I did a snapshot, it would always keep the very last copy of the machine. But NOT in this case. So I am really dazzled.
Can you give some hint on what could happen? Is it normal that AWS deletes data (DDBB + folder and files) when changing instance type? Do you think it might have to do with IAM policies?
Thank you
The EC2 user guide has information about the EC2 Storage options. To summarise:
The EC2 instance store volume is erased when the instance is stopped or terminated.
In contrast, EBS (Elastic Block Storage) can be mounted to a running EC2 instance (c.f. a physical hard drive). EBS volumes can be detached from one instance and attached to another instance. Moreover, you can create a snapshot of an EBS volume that is stored in S3 and you can recreate EBS volumes from that snapshot that can be attached to other EC2 instances.
The EC2 user guide provides step by step instructions:
Restoring an Amazon EBS Volume from a Snapshot
Attaching an Amazon EBS Volume to an Instance
Lastly, no, this behaviour is not related to IAM policies.
I'm trying AWS auto-scaling for the first time, as far as I understand it creates instances if for example my CPU Utilization reaches critical level, that I define.
So I am curious, after I lunch my instance I spend a fair amount of time configuring it and copying the data, if AWS auto-scales my instance how will it configure the new instances and move the data to it?
You can't store any data that you want to keep on an instance that is part of an autoscaling group (well you can, but you will lose it).
There are (at least) two ways to answer your question:
Create a 'golden image', in other words spin-up an instance, configure it, install the software etc and then save it as an AMI (amazon machine image). Then tell the autoscaling group to use that AMI each time an instance starts - it will be pre-configured when it starts.
Put a script on the instance that tells the instance how to configure itself when it starts up (in the user data). SO basically each time an instance scales up, it runs the script and does all the steps it needs to to configure itself.
As for you data, best practice would be to store any data you want to keep in a database or object store that is not on the instance - so something like RDS, DynamoDB or even S3 objects.
You could also use AWS EFS, store there your data/scripts that the EC2 Instances will be sharing, and automatically mount it every time a new EC2 Instance is created via /etc/fstab.
Once you have configured the EFS to be mounted on the EC2 Instance (/etc/fstab), you should create a new AMI, and use this new AMI to create a new Launch Configuration and AutoScaling Group, so that the new Instances automatically mount your EFS and are able to consume that shared data.
https://aws.amazon.com/efs/faq/
Q. What use cases is Amazon EFS intended for?
Amazon EFS is designed to provide performance for a broad spectrum of
workloads and applications, including Big Data and analytics, media
processing workflows, content management, web serving, and home
directories.
Q. When should I use Amazon EFS vs. Amazon Simple Storage Service (S3)
vs. Amazon Elastic Block Store (EBS)?
Amazon Web Services (AWS) offers cloud storage services to support a
wide range of storage workloads.
Amazon EFS is a file storage service for use with Amazon EC2. Amazon
EFS provides a file system interface, file system access semantics
(such as strong consistency and file locking), and
concurrently-accessible storage for up to thousands of Amazon EC2
instances. Amazon EBS is a block level storage service for use with
Amazon EC2. Amazon EBS can deliver performance for workloads that
require the lowest-latency access to data from a single EC2 instance.
Amazon S3 is an object storage service. Amazon S3 makes data available
through an Internet API that can be accessed anywhere.
https://docs.aws.amazon.com/efs/latest/ug/mount-fs-auto-mount-onreboot.html
You can use the file fstab to automatically mount your Amazon EFS file
system whenever the Amazon EC2 instance it is mounted on reboots.
There are two ways to set up automatic mounting. You can update the
/etc/fstab file in your EC2 instance after you connect to the instance
for the first time, or you can configure automatic mounting of your
EFS file system when you create your EC2 instance.
I recommend using a shared data container if it is data that is updated and the updated data is needed by all instances that might be spinning up.
If it is database data or you could store the needed data in a database I would consider using an RDS.
If it is static data only used to configure the instances like dumps or configuration files which are not updated by running instances then I would recommend pulling them from CloudFlare or S3 of iT is not possible to pull them from a repository.
Good luck
Last day I wanted, according to AWS recommendations, put my ec2 instance inside of an autoscaling group. I created my ec2 instance by using the standard linux AMI instance and then I installed a full LAMP server.
The next morning I tried accessing my apache and guess what? My LAMP wasn't there anymore! Everything was wiped away.
I guess this is because, for some reason, the autoscaling group deleted my instance and recreated it vanilla.
Now I still want to autoscale my instance but, of course, I want to keep my LAMP and the stored data.
So here's my questions:
How to create a customized image starting from my actual instance?
Would it be correct to create the mysql DB using AWS RDS so to not keep it linked to my instance?Is it more or less expensive than dedicating a EBS storage?
I also want to keep my /var/www/html data somewhere shared between instances: while it is true that, on production, I won't update those files often it is also true that I don't want to lose them just because the autoscaling resets my instance state. I also don't want to re-create an image each time I update said files... What's the best way?Maybe an s3 bucket? Or, still, an EBS storage shared between instances?
I would assume that the reason that your "LAMP [server] wasn't there anymore" was because the web server failed health checks and was terminated and replaced by AutoScaling.
Elastic Beanstalk would be a good way to manage some of the complexity here. If that's not an option then you should read up on AutoScaling, ALB, and health checks.
In response to your specific questions:
you can create an Amazon Machine Image (AMI) from an instance. When you, or AutoScaling, launch a new instance from that AMI, you can get the instance up to date by running a script in userdata
move the DB from the web/app server to RDS, or to a DB server that you manage yourself
maintain the html/js/css etc. in S3 and sync them to your web server periodically (there are other options, but that's simple)
I have a php/mysql website that I want to deploy on AWS. Ultimately, I'm going to want auto-scaling (but don't need it right away).
I'm looking at an EBS based AMI. I see that by default the "Root Device Volume" is deleted when an instance "terminates". I realize I can also attach other EBS devices/drives to an instance (that will persist after termination) but I'm going to save most user content in S3 so I dont think that's necessary. I'm not sure how often I'll start/stop vs when i would ever want to terminate. So that's a bit confusing.
I'm mostly confused with where changes to the system get saved. Say I run a YUM install or update. Does that get saved in the "root device volume"? If i stop/start the instance, the changes should be there? What about if I setup cron jobs?
How about if I upload files? I understand to an extent that it depends where I put the files and if I attached a second EBS. Say I just put them in the root folder "/" (unadvised, but for simplicity sake). I guess that they are technically saved in the "root device volume"? If I start/stop the instance, they should still be there?
However, if I terminate an instance, then those changes/uploads are lost. But if I set the "root device volume" to not delete on termination, then I can launch a new instance with the changes there?
In terms of auto-scaling. Someone said to leave the "root device volume" to default delete so that when new instances are spun up/shut down, they don't leave behind zombie EBS volumes that are no longer needed (and would require manual clean-up)?
Would something like this work: ?
Setup S3 bucket (for shared image uploads)
Setup Amazon RDS / mysql
Setup DynamoDB (for sharing php sessions)
Launch EBS-backed AMI (leave as default to delete "root device volume" on
termination). Make system updates using yum/etc. Upload via sftp
PHP/HTML/JS/CSS files (ex: /var/www/html). Validate site can save
images to S3, share sessions via DynamoDB, access mysql via RDS.
Make/clone your own AMI image from your currently running/configured
one. Save it with a name that indicates site version/date/etc.
Setup auto-scaling to launch the image created in #5
I'm mostly concerned with how to save my configuration so that 1) changes are saved in-case i ever need to terminate an instance (before using autoscale) and 2) that auto-scaling will have access to the changes when I'm ready for it. I also don't want something like the same cron-job running on all auto-scaling instances.
I guess I'm confused with "does creating my own AMI image in #4" basically replace the "saving EBS root device volume" on termination? I can't wrap my head around the image part of things vs the storage part of things.
I get even more confused when I read about people talking about if you use "Amazon Linux" then the way they deploy updates every 6 months makes it difficult to use because you are forced to use new versions of software. How does that affect my custom AMI (with my uploaded code)? Can I just keep running yum updates on my custom AMI (for security patches) and ignore any changes to amazon's standard AMIs? When does the yum approach put me at risk for being out-of-date?
I know there are a host of things I'm not covering (dns/static IPs/scaling metrics/etc). That instead of uploading files then creating an AMI image, some people have their machine set to pull files from git on startup (i dont mind my more manual approach for now). Or that i could technically put the php/html/css/js on S3 too.
Sorry for all of the random questions. I know my question might not even be totally clear, but I'm just looking for confirmation/advice in-general. There are so many concepts to tie-together.
Thanks and sorry for the long post!
Yes, if you install packages, upload files, set up cron jobs, etc. and then stop the EBS-based instance, everything will still be there when you restart it.
Consequently, if you create an AMI from that instance and then use it for your autoscaling group, all the instances of the autoscaling group will run the cron jobs.
Your steps look good. As you are creating an AMI, your changes will be saved in that AMI. If the instance is terminated, it can be recreated via the AMI. The modifications made on that instance since the AMI creation will not be saved though. You need to create an AMI or take a snapshot of the EBS volume if you want a backup.
If you make a change and want to apply it to all the instances in the autoscaling group, you need to create a new AMI and apply it to your autoscaling group.
Concerning the cron jobs, I guess you have 2 options:
Have 1 instance that is not part of the autoscaling group running them (and disable the cron jobs before creating the AMI for the autoscaling group)
Do something smart so only one instance of the autoscaling group runs them. Here is the first page I hit on Google: https://gist.github.com/kixorz/5209217 (not tested)
Yes, creating your own AMI image basically replaces the "saving EBS root device volume" on termination.
An EBS boot AMI is an EBS snapshot of the EBS root volume plus some
metadata like the architecture, kernel, AMI name, description, block
device mappings, and more.
(From: AWS Difference between a snapshot and AMI)
Yes, you can automatically run yum security updates. To be completely identical to the latest Amazon Linux AMI, you should run all yum updates (not only security). But I wouldn't run those automatically.
Let me know if I forgot to answer some of your questions or if some points are still unclear.